PhD Defense: "Nonpolar m-plane GaN-Based Laser Diodes in the Blue Spectrum"

Kate Kelchner

March 22nd (Thursday), 11:00am
Elings Hall, Room 1601

Gallium nitride (GaN), together with its alloys with aluminum and indium, have revolutionized the solid-state optoelectronics market for their ability to emit a large portion of the visible electromagnetic spectrum from deep ultraviolet and into the infrared. GaN-based semiconductor laser diodes (LDs) with emission wavelengths in the violet, blue and green are already seeing widespread implementation in applications ranging from energy storage, lighting and displays. However, commercial GaN-based LDs use the basal c-plane orientation of the wurtzite crystal, which can suffer from large internal electric fields due to discontinuities in spontaneous and piezoelectric polarization that limits device performance. Nonpolar GaN benefits from the lack of polarization-induced electric fields as well as enhanced anisotropic gain. In this talk, we will discuss some of the benefits and limitations of m-plane oriented nonpolar GaN for LD applications in the true blue spectrum (450 nm). Topic will include an overview of material growth by metal-organic chemical vapor deposition (MOCVD), waveguide design and processing techniques for improving device performance for multiple lateral mode and single lateral mode ridge waveguides.

Hosted by: Professor Steven P. DenBaars